Malic acid diester surfactants

Abstract

This invention provides water-based compositions, particularly coating, ink, fountain solution, adhesive and agricultural compositions, manifesting reduced equilibrium and dynamic surface tension by the incorporation of a surface tension reducing amount of certain malate diester compounds of the structure where R 1 and R 2 are C3 to C6 alkyl groups.

1. In a method for applying a coating of a water-based composition to a surface to partially or fully coat the surface, the composition comprising an aqueous medium which is at least 90 wt % water and containing an inorganic or organic compound and an effective amount of a surfactant for reducing the dynamic surface tension of the composition, the improvement which comprises employing as the sufactant a malate diester of the structure 
                 
 
       where R 1  and R 2  are C3 to C6 alkyl groups. 
     
     
       2. The method or  claim 1  in which the water-based composition is selected from the group consisting of aqueous organic coating, ink, adhesive, fountain solution and agricultural compositions and the malate diester is present at 0.001 to 20 wt % of the water-based composition. 
     
     
       3. The method of  claim 2  in which an aqueous sotutlen of the instate diester demonstrates a dynamic surface tension of less than 45 dynes/cm at a concentration of ≦5 wt % in water at 25° C. and 6 bubbles/second according to the maximum-bubble-pressure method. 
     
     
       4. The method of  claim 1  in which R 1  and R 2  are the same. 
     
     
       5. The method of  claim 4  in which R 1  and R 2  are a C4 alkyl group. 
     
     
       6. The method of  claim 4  in which R 1  and R 2  are a C5 alkyl group. 
     
     
       7. The method of  claim 4  in which the alkyl group has terminal branching. 
     
     
       8. The method of  claim 4  in which the alkyl group is isobutyl. 
     
     
       9. The method of  claim 4  in which the alkyl group is n-butyl. 
     
     
       10. The method of  claim 7  in which the ester is derived from a primary alcohol. 
     
     
       11. The method of  claim 3  in which the measurement is made at 20 bubbles/second. 
     
     
       12. An aqueous composition comprising in an aqueous medium which is at least 90 wt % water an inorganic compound which is a mineral ore or a pigment or an organic compound which is a pigment, a polymerizable monomer, an of igometic resin, a polymeric resin, a detergent, a herbicide, an insecticide, a fungicide, or a plant growth modifying agent and an effective amount of a malate diestor for reducing the dynamic surface tension of the composition, the malato diester having the structure: 
                 
 
       where R 1  and R 2  are a C3 to C6 alkyl group. 
     
     
       13. The aqueous composition of  claim 12  in which an aqueous solution of the malate diester demonstrates a dynamic surface tension of less than 45 dynes/cm at a concentration of ≦5 wt % in water at 25° C. and 6 bubbles/second according to the maximum-bubble-pressure method and the malate diester is present at 0.01 to 10 wt % of the aqueous composition. 
     
     
       14. The aqueous composition of  claim 12  in which R 1  and R 2  are a C4 alkyl group. 
     
     
       15. The aqueous composition of  claim 12  in which R 1  and R 2  are a C5 alkyl group. 
     
     
       16. The aqueous composition of  claim 12  in which the alkyl group has terminal branching. 
     
     
       17. The aqueous composition of  claim 16  in which the ester is derived from a primary alcohol. 
     
     
       18. The aqueous composition of  claim 12  in which the alkyl group is isobutyl. 
     
     
       19. The aqueous composition of  claim 12  in which the alkyl group is n-butyl. 
     
     
       20. The aqueous composition of  claim 13  in which the measurement is made at 20 bubbles/second.